(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Emissions of sulphur oxides, particulates and trace elements in the Sudbury basin : Sudbury Environmental Study, SES 008/82 /"

SUDBURY ENVIRONMENTAL STUDY 









^ EMISSIONS OF SULPHUR OXIDES, PARTICULATES 
AND TRACE ELEMENTS IN THE SUDBURY BASIN. 



■i •*■'.*» ^ 



S '■ 






'■V, 



SES 008/82 



FALL 1982 




Ministry 
of the 
Environment 



The Honourable 
Keith C. Norton, Q.C., 
Minister 

Gerard J. M. Raymond 
Deputy Minister 



j^j.,. 



Js'^^^^t'sii^**; ■- 



uniano 



':.:f. 






SUDBURY ENVIRONMENTAL STUDY 

EMISSIONS OF SULPHUR OXIDES, PARTICULATES AND TRACE 
ELEMENTS IN THE SUDBURY BASIN. 



SES 008/82 



by 



V. Ozvacic 

Source Assessment Unit 

Emissions Technology and Regulation 

Development Section, Air Resources Branch 

Ontario Ministry of the Environment 

880 Bay Street, 4th Floor 

Toronto, Ontario, Canada, M5S Iz 8 



October 1982 



S.E.S. Coordination Office 

Ontario Ministry of Environment 

6th Floor, 40 St. Clair Ave. W. 

Toronto, Ontario, Canada, M4V 1M2 

Project Coordinator: E, Pich§ 



SES 008/82 

ISBN 0-7743-7270-2 

ARB-ETRD-09-82 



Copyright Provisions and Restrictions on Copying: 

This Ontario Ministry of the Environment work is protected by Crown 
copyright (unless otherwise indicated), which is held by the Queen's Printer 
for Ontario, It may be reproduced for non-commercial purposes if credit is 
given and Crown copyright is acknowledged. 

It may not be reproduced, in all or in part, part, for any commercial purpose 
except under a licence from the Queen's Printer for Ontario. 

For information on reproducing Government of Ontario works, please 
contact Service Ontario Publications at copvright@ontario.ca 



TABLE OF CONTENTS 

Page 

List of Tables i 

List of Figures li 

Acknowledgements iii 

1. Introduction 1 

2. Summary 5 

3. Description of Sources and Processes 9 

3.1 General 9 

3.2 The Inco 381 m Stack and the Smelter 

Building at Copper Cliff 9 

3.2.1 Copper Circuit 10 

3.2.2 Nickel Circuit 11 

3.3 The Inco 19^^ m Stack and the Iron Ore 

Recovery Plant Complex at Copper Cliff 12 

3.3.1 Iron Ore Recovery and Pelletizer Plants 13 

3.3.2 Nickel Refinery m 

3.3.3 Sulphuric Acid Plants 15 

3 A The Falconbridge 93 m Stack 15 

^. Discussion of Emission Measurement Methods, Their 

Frequency and Accuracy 17 

5. Sulphur Dioxide Emissions 22 

5.1 The Inco 381 m Stack 23 

5.2 Inco Low Level Emissions 28 

5.3 The Inco 19^ m Stack 29 
5A The Falconbridge 93 m Stack 30 



TABLE OF CONTENTS - Continued 

Page 

6. Emissions and Size of Total Particulates 32 

6.1 The Inco 381 m Stack 13 

6.2 The Inco 19^^ m Stack M 

6.3 The Falconbridge 93 m Stack $Q 
6A Inco's Low Level Emissions 4l 
6.5 Size of Emitted Particulates ft2 

6.5.1 Particulate Size Measurements at 

the Inco 381 m Stack 43 

6.5.2 Particulate Size Measurements at 

the Falconbridge 93 m Stack ^i 

7. Emissions of Metals i|6 

7.1 The Inco 381 m Stack 48 

7.2 The Inco 19* m Stack 58 

7.3 Low Level Emission from the Inco Smelter 

Building 60 

7 A The Falconbridge 93 m Stack f 1 

8. Emissions of Sulphuric Acid 65 

9. References 67 



- 1 - 



LIST OF TABLES 

TITLE PAGE 

1. AVERAGE YEARLY EMISSIONS OF MAJOR POLLUTANTS IN THE 
SUDBURY BASIN IN TONNES FOR THE PERIOD 1973-1981 6 

2. YEARLY EMISSIONS OF SULPHUR DIOXIDE FROM MA30R INDUSTRIAL 
SOURCES IN THE SUDBURY BASIN IN THOUSAND TONNES 23 

3. SULPHUR DIOXIDE EMISSIONS FROM INDIVIDUAL PROCESSES TO THE 
INCO 19^^ METRE STACK IN TONNES PER/DAY IN 1977 30 

^. YEARLY EMISSIONS OF TOTAL PARTICULATES IN TONNES FROM 
MAJOR INDUSTRIAL SOURCES IN THE SUDBURY BASIN FROM 
1973 TO 1981 33 

5. MEASURED AVERAGE PARTICULATE EMISSIONS FROM THE INCO 381 M 
STACK IN TONNES/HOUR 35 

6. PARTICULATE EMISSIONS FROM THE INCO 194 M STACK 

IN TONNES/DAY 39 

7. SUMMARY OF PARTICLE SIZE MEASUREMENTS AT THE INCO 

381 M STACK «4 

8. SIZE OF PARTICULATES EMITTED FROM THE FALCONBRIDGE 

93 M STACK 45 

9. AVERAGE EMISSIONS OF METALS FROM MAJOR SUDBURY 

SOURCES IN KILOGRAMS/HOUR 47 

10. AVERAGE EMISSIONS OF FIVE MAJOR METALS FROM THE INCO 381 M 
STACK IN KILOGRAM/HOUR ^9 

11. AVERAGE MEASURED EMISSIONS OF METALS AND OTHER 
PARTICULATE POLLUTANTS FROM THE INCO 381 M STACK IN 
KILOGRAMS/HOUR 57 

12. COMPARISON OF IN-STACK AND IN-PLUME AVERAGE EMISSIONS 

IN TONNES/DAY 59 

13. EMISSIONS OF METALS FROM THE IRON ORE RECOVERY AND 

NICKEL REFINERY PLANTS IN KILOGRAMS/DAY $0 

14. AVERAGE LOW LEVEL EMISSIONS OF METALS FROM THE 

INCO SMELTER AT COPPER CLIFF DURING TYPICAL PRODUCTION 

RATES OF NICKEL BESSEMER MATTE AND BLISTER COPPER 

IN KILOGRAMS/DAY ^2 

15. EMISSIONS OF METALS FROM THE FALCONBRIDGE 93 M 

STACK IN KILOGRAMS/DAY ^ 

16. ACID EMISSIONS FROM MAJOR INDUSTRIAL SUDBURY SOURCES 

IN TONNES/HOUR $6 



- 11 - 



LIST OF FIGURES 



TITLE PAGE 



1. LOCATION OF MAJOR AIR POLLUTION SOURCES IN THE 
SUDBURY BASIN IN ONTARIO 3 

2. SULPHUR DIOXIDE EMISSIONS COMPUTED BY MASS 
BALANCE VS EMISSIONS MEASURED AT THE INCO 

381 M STACK 24 

3. SO2 EMISSIONS VS ROASTER MATERIAL INPUT 26 

4. SO2 EMISSIONS VS CONVERTER MATTE INPUT 27 

5. TOTAL PARTICULATE VS SULPHUR DIOXIDE EMISSIONS 37 

6. FREQUENCY DISTRIBUTION OF ERRORS FOR PARTICULATE VS 
SULPHUR DIOXIDE EMISSIONS 38 

7. IRON VS SULPHUR DIOXIDE EMISSIONS 51 

8. FREQUENCY DISTRIBUTION OF ERRORS FOR IRON VS SULPHUR 
DIOXIDE EMISSIONS 52 

9. COPPER VS SULPHUR DIOXIDE EMISSIONS 53 

10. FREQUENCY DISTRIBUTION OF ERRORS FOR COPPER VS SULPHUR 
DIOXIDE EMISSIONS 54 

11. NICKEL VS SULPUR DIOXIDE EMISSIONS ^5 

12. FREQUENCY DISTRIBUTION OF ERRORS FOR NICKEL VS SULPHUR 
DIOXIDE EMISSIONS 56 



- Ill - 



ACKNOWLEDGEMENTS 



This report is based on results published in many reports, and appreciation 
is extended to all individuals whose efforts have made this report possible. 

Personnel from various process technology groups and laboratories of the 
Inco Metals Company and Falconbridge Limited, and Sudbury Regional Office, 
Laboratory Services Branch and Air Resources Branch staff of the Ministry of 
the Environment contributed to the generation of the data compiled and 
discussed herein. 

Special thanks are extended to Messrs, G. Wong and J. Marson for 
performing calculations for this report, Messrs. R. Potvin, L, Fitz, E.T. Barrow, 
C.B. Martin, Drs. M, Lusis and W. Chan for their critical review of this report. 



-I- 

1. INTRODUCTION 

The Sudbury Basin in Ontario is an area of major environnnental interest 
because of large emissions of sulphur dioxide and particulates due to smelting 
and mining activities. In 1973, the Ontario Ministry of the Environment 
recognized the need for an evaluation of the impact of the smelting industries on 
the area and initiated studies aimed at characterization of emissions, in terms of 
both chemical composition and quantities, from the most significant sources in 
the Basin. In 1977, a more comprehensive program was established at the Air 
Resources Branch with the following objectives: 

1. to define the sources and source strengths of atmospheric emissions 

in the Sudbury Basin. 
2* to determine the fate of these emissions. 
.% to determine the ambient air concentrations of potentially hazardous 

substances. 

In essence, the study problem was the origin and fate of the pollutants, the 
nature and quantity of the emissions, and then dispersion, chemical 
transformation and ultimate deposition subsequent to being released to the 
atmosphere. A more detailed description of the program is given in the Ministry 
report ARB-27-82 ARSP (39). 

This report deals with the emissions. The major emission sources in the 
Basin are described in detail and the emissions of pollutants are quantified on the 
basis of many reports issued in the last ten years by the companies which own 
the processing plants in the area and the Ministry of the Environment. 

The processing plants with the major air pollution sources in the Sudbury 
Basin are all located within a distance of 15 kilometres from the city of Sudbury. 



-2- 

(the location of these plants is illustrated in Figure 1). They are associated with 
two copper and nickel smelters (Inco Metals Company at Copper Cliff and 
Falconbridge Limited in the town of Falconbridge) and the Inco Metals Company 
nickel refinery - iron ore recovery plant complex at Copper Cliff, Emissions 
from these sources account for almost all industrial emissions in the Basin. 

During the eight years from 1973 to 1980, emissions from a number of 
individual sources at both smelters were measured by the companies and 
governments, and the combined emissions from these sources have been 
considered as representative of all industricil emissions in the Basin. Most of the 
emission measurements were done in stacks or ducts venting plant emissions to 
these stacks. In the case of Inco, emissions escaping from the main smelter 
building through windows and building ventilators were also measured. 

A variety of measurement methods suited to a particular source or stack 
were employed by various industry or government groups. These methods ranged 
from rigorous source testing procedures as specified by the Ministry of the 
Environment to unproven and experimental emission measurement techniques. 
The observed inconsistencies and differences in the measured results were 
partially attributed to the nonre present at iveness of some measurement methods. 

Besides differences in the measurement methods applied at the same 
source at various times, there were differences in the process conditions, and 
particularly in the amount of materials processed in the measured plants. The 
variations in the process conditions effected variations in the emission rates and 
the results of the emission measurements. However, due to complexity of the 
processes involved in smelting, there were difficulties in relating the effects of a 
specific process (or changes in the operation of this process) on the totcU 



-3- 




FIGURE I. LnCRTlDN DP MRJDR RIR PDLLUTIDN 
BQURCEB IN THE SUDBURY BR51N IN 
DNTRRID 



- '^ - 

emissions from the smelter or the plant. This in turn resulted in difficulties in 
the analyses of the results measured at the same source at different times and in 
arriving at the emissions rate which is most representative of the process. 

The purpose of this report is to summarize and discuss all emission testing 
carried out during the period from 1973 to 1980, interpret and correlate the 
measured emissions with production wherever possible, and provide a technical 
basis for estimation of emissions in the Sudbury Basin, This in turn is necessary 
for the evaluation and analysis of air pollution in the Basin and consideration of 
any abatement action by the industries of concern. 



- 5- 

2. SUMMARY 

The most significant source of air pollution in the Sudbury Basin is the 381 
metre stack at the Inco Copper Cliff smelter. Depending on the pollutant, this 
source may contribute anywhere from 50% to over 80% of all emissions in the 
Basin. The only exception is copper, which is also emitted in significant 
quantities from other sources. In order of emission magnitude the other sources 
of significant pollution in the area are the Inco 19^^ metre stack, the 
Falconbridge 93 metre stack, and finally ventilators and windows which emit 
unconfined emissions from Inco's main smelter building at Copper Cliff. 

Emissions of almost all major pollutants from the Inco 381 m stack 
increase proportionately with production activities in the smelter. It was 
possible to demonstrate this relationship for this source because of the relatively 
large number of measurements performed in the period from 1973 to 1980. 
Corresponding data for the other sources in the Basin were not sufficient for a 
similar experimental verification. 

Emissions of selected major pollutants from the measured sources in the 
Sudbury area are shown in Table 1. Maximum, average and minimum emissions 
are shown wherever available. 

Emissions of sulphur dioxide from the Inco 381 m stack have been measured 
on a continuous basis since 1973, and were shown to change proportionately with 
the level of production. The emissions of particulates, iron, nickel, and copper 
from this stack as shown in Table 1 were calculated from linear correlations 
between the measured emissions of sulphur dioxide and these species such that 



TABLE 1: YEARLY EMISSIONS OF MA30R POLLUTANTS IN THE SUDBURY BASIN 

IN TONNES FOR THE PERIOD 1973 - 1981 



Source 


Variation 


Sulphur 
dioxide 


Sulphuric 
acid 


Total 
particulate 


Iron 


Copper 


Nickel 


Lead 


Arsenic 


Inco 381 m 
Stack* 


Maximum 
Average 
Minimum 


1,185,449 
885,667 
383,000 


14,541 
7,270 
3,241 


14,494 

11,417 

6,491 


1,454 
990 
201 


350 

245 

70 


342 

228 

53 


298 

184 

88 


201 

114 
70 


Inco 194 m 
Stack 


Maximum 
Average 
Minimum 


104,390 
54,568 
18,980 


1,664 


2,380 


643 


171 


226 


6 


4 


[nco Smelter 
(Low Level) 


Maximum 
Average 
Minimum 


16,000 

12,000 

6,000 


88 


586 
283 


90 
34 


312 
242 

117 


40 
31 
15 


0.8 
0.6 
0.3 


0.1 
0.1 
0.1 


-alconbridge 

191 m 
Stack 


Maximum 
Average 
Minimum 


274,000 

173,000 

88,000 


438 


865 


98 


11 


9.6 


13.4 


6.4 


Inco** 

Two 45 m 

Stack 


Average 


- 


- 


(4,073) 


(2,354) 


- 


- 


- 


- 


TOTAL 


Average 


1,125,235 


9,460 


15,248 


1,801 


669 


500 


204 


125 



Basis: 365 days x 24 hrs/day production. 



* 
o 



Oxides of nitrogen emissions expressed as NO- = 3,281 tonnes. 

Hydrogen chloride emissions = 530 tonnes. 

Emissions of particulates, iron, copper and nickel from the 381 m stack are yearly values calculated from correlations 

with sulphur dioxide emissions. Emissions of sulphuric add, lead and arsenic are average measured values. 

Emissions ceased in April 1980, not included in average. 

Except for INCO Smelter (low level), all sulphur dioxide emissions were obtained by mass balance calculations. 

Annual low level ammonia emissions from Inco's iron ore recovery plant in 1977 was 4,219 tonnes. 



I 



-7- 

they correspond to annual sulphur dioxide emissions. In this way, the effect of 
production rates on emissions has been taken into account, and so the calculated 
emissions as shown in Tables 1 and 10 are considered more representative of the 
actual emissions than the individucil emissions measured in stack tests of short 
duration shown in Table 11. Before selecting the straight-line correlations, a 
number of linear and nonlinear relations were examined for the goodness of fit 
through the experimental points plotted on the graphs. In the case of iron, 
copper and nickel, the straight lines and exponentied curves provided reasonable 
correlations of the data available; however, since the estimates from these 
functions were not significantly different, it was decided to use the 
mathematically simpler straight-line correlations. As is the case with any 
function fitted through scattered experimental points, errors (or uncertainties) 
are associated with the estimates of emissions of particulates, iron, copper and 
nickel, calculated from the straight-line correlations in this report and these 
errors must be taken into account when using the calculated emissions. In any 
individual case, the variation from the straight-line estimate can be greater than 
+ 100%, but is generally less than +75%. The indicated maximum, average, and 
minimum in Table 1 are yearly values. Emissions during shorter periods in any of 
the examined eight years could be either smaller or larger, depending on 
production. Emissions from the other sources in Table 1 were measured in 
shorter periods and are in some cases based on the results of one test only. 

About 78% of all sulphur dioxide and 11% of all sulphuric acid emissions 
are from the Inco 381 m stack; the estimates of total particulates indicate that 
the corresponding contribution from this source is lower at 75^, while the 
contributions to metal emissions are still smaller at 37-55% except for lead, and 
arsenic which are mostly emitted from this source. 

Up to April 1980, when the pelletizing plant, associated with the iron ore 



-8- 

recovery process was shut down, Inco's two ^5 m stacks at this plant were 
significant sources of particulate and iron emissions in the Basin. The best 
available emission data are based on a single testing survey of only one stack. 
Hence, due to the paucity of data for this source, the emission rates presented in 
Table I were not included in the average emissions from the Sudbury Basin. This 
source is not expected to resume operation. 

Emissions of oxides of nitrogen and hydrogen chloride were measured on 
two occasions at the Inco 381 m stack, and because they were small in 
comparison to sulphur dioxide and sulphuric acid, these measurements were 
discontinued at this and other stacks in the Basin. 

Ammonia emissions are low level emissions, occurring through losses to the 
atmosphere via leaching and recovery buildings' ventilators. They are calculated 
from losses in process and discharge streams on a monthly basis. Annual 
emission for 1977 was the only available estimate at the time of writing. 

The size of the emitted particulates is an important consideration in the 
understanding the deposition of particulate pollutants and in determining the 
airborne part of particulate emissions. Since most sources in the Sudbury Basin 
are controlled and the majority of particulates are removed by electrostatic 
precipitators at a source, it was expected and confirmed by testing that large 
portions of the particulates in emissions are less than 10 micrometers (m |j ) in 
diameter. 



-9- 
3. DESCRIPTION OF SOURCES AND PROCESSES 

3.1 GENERAL 

The most significant sources of industrial emissions in the Sudbury Basin 
are five stacks - the Inco 381 m and 19^ m stacks, the Falconbridge 93 m, and 
prior to 1980, Inco's two ^5 m stacks. Before entering these stacks, emissions 
from various industrial processes are cleaned of a large portion of particulate 
pollutants by electrostatic precipitation and contain small and to a large extent 
airborne particulates. These are called confined emissions, which after being 
discharged are mostly carried away from stacks and are diluted considerably 
with ambient air before impinging on the ground. Other emissions are 
unconfined, since they escape various process fume collection steps in the ore 
and metal processing. They are emitted through small stacks on building roofs, 
windows and ventilators, and called low level emissions, impacting in the plant 
vicinity and reaching the ground in a more concentrated form. They are difficult 
to quantify and were measured by the company at Inco's Copper Cliff smelter 
building only. However, this building is the most significant source of low level 
emissions in the Sudbury Basin. 

A detailed description of the processes described in this chapter was 
presented in an earlier Ministry report (2^). The following is intended as a 
summary of that information. 



3.2 INCO'S 381 M STACK AND THE SMELTER BUILDING AT COPPER CLIFF 

The 381 m stack emits gases from pyrometallurgical smelting processes at 
Inco's Copper Cliff smelter. The outside diameters of this stack at the base and 



- 10- 



at the top are 35.5 m and 15.8 m, respectively. About 157,000 cubic meters of 
gas at a temperature of 130°C are emitted each minute from this stack. The gas 
temperature increases with increasing production rates and can reach about 
175 C when the smelter is operated at full capacity. Gases are received from 
various processes via two inlet breachings situated opposite to each other at the 
stack base, and are cleaned of most of the particulate pollutants by electrostatic 
precipitators called Cottrells prior to entering the stacks. 



Because of the large stack diameter, the positions of the two inlet 
breachings and the location of the existing sampling platform, strict emission 
measurements at this stack are long lasting, manpower intensive and expensive. 
On occasions, the measurement methods were simplified at a cost of somewhat 
reduced accuracy. 

The purpose of the smelting processes which emit pollution into this stack 
is to make nickel and copper of appropriate purity in the form of nickel bessemer 
matte and blister copper from suitably prepared ore concentrates. There are 
two main circuits with associated process equipment - one of each for nickel and 
copper. Nickel matte processing is considered a separate process, however, 
since in comparison to ore roasting and smelting, it is not a major source of 
emissions, this process will not be discussed any further. 

3.2.1. COPPER CIRCUIT 

Copper concentrate, mixed with sand, is smelted in a flash furnace, 
producing copper matte, slag , and sulphur dioxide at about Z0% concentration in 
the off-gases. These gases are first cleaned in scrubbers and a wet electrostatic 
precipitator, then sent to the sulphur products plant for the production of liquid 
sulphur dioxide. In case of an emergency, these gases may be directed to the 381 
m stack via a bypass system. The gases rising from the handling operations of 



- 11 - 

the two melted products - slag and copper matte - are split, with the major 
portion being emitted via a small stack on the roof of the building and the rest 
directed to the 381 m stack. In addition to these major emissions, there are 
fugitive emissions resulting from leakages in the scrubbers, sulphur dioxide 
release from the scrubber liquid, temporary pressure increases in the furnace and 
the periodic return of the converter slag. 

Copper matte from this furnace is charged to copper converters to 
eliminate the remaining iron and to produce blister copper which is then sent to 
copper refinery for further refining. Converting is a batch process in which 
oxygen enriched air is blown through the melted charge to produce oxides of iron 
which react with silica and form slag. The main product of converting, blister 
copper, is sent to the copper refinery for further processing. The main portion 
of off-gases is sent to the 381 m stack via collection fume hoods and flues. Part 
of the off-gases escapes from around the collecting hoods into the building and 
outside through the roof ventilators as fugitive emissions. 

3.2.2 NICKEL CIRCUIT 

Nickel concentrate is first mixed with sand and then roasted in multi- 
hearth roasters to remove moisture and a part of sulphur as sulphur dioxide. 
Heating of concentrate on the roaster hearths is accomplished by the combustion 
of natural gas and the oxidation of iron sulphide with air. This air along with 
sulphur dioxide and entrained particulates is directed to the 381 m stack via 
piping arrangements on the roasters' tops. Besides these confined emissions, 
there are periodic fugitive emissions escaping through the inspection doors. 
These emissions rise to and are emitted through the roof ventilators and the 
building windows. Six roasters are operated in conjunction with one 
reverberatory furnace. 



- 12- 

The product of roasting, calcine, is fed to the reverberatory furnaces to 
combine iron oxide with silicate and produce slag. Slag floats on the top of 
matte which contains heavier sulphides of copper, nickel and iron. Combustion 
of oil, sustained with oxygen enriched air, provides the necessary heat to 
maintain the furnace contents in a molten state. The combustion gases with 
entrained particulates and sulphur dioxide are conveyed via a reverb-header flue 
to the 381 m stack. Unconfined fugitive emissions from this furnace originate 
during the removal of matte and slag from the furnace, they are collected by 
hoods and exhausted into separate vents. In addition, puffing emissions, escaping 
the furnace through its brickwork during periods of increased pressure within the 
furnace, and the emissions originating during the converter slag removal exit the 
smelter building via the roof ventilators above the furnace. There are five 
reverberatory furnaces of which three or four are usually operated at any one 
time. 

Matte from these furnaces is fed to the nickel converters, where similar 
operations to those in copper converting are carried out. After oxidation of iron 
and formation of slag, the converter is rotated for skimming and discharging of a 
high grade copper-nickel matte for casting and cooling. Emissions from various 
steps - charging, blowing, skimming and pouring - are collected by hoods and 
directed to the electrostatic precipitators and the 381 m stack. However, some 
of these emissions escape around the hoods and from the building via ventilator 
openings. Fourteen converters are normally used in the nickel circuit. 



3.3 THE INCO 19» M STACK AND THE IRON ORE RECOVERY PLANT 
COMPLEX AT COPPER CLIFF 



The Inco 19^ m stack is the second largest source of industrial emissions in 



- 13 - 

the Sudbury Basin. Approximately 9500 cubic meters of gas at 150°C to 200°C, 
containing metals, sulphur dioxide, and sulphuric acid are exhausted every 
minute from this stack. The stack receives off-gases from Inco's iron ore 
recovery plant, nickel refinery and three sulphuric acid plants. Similarly to 
process off-gas treatment at the nickel smelter, emissions from these five plants 
are cleaned of the majority of entrained particulates prior to entering the stack. 
Cyclones, scrubbers, settling chambers, electrostatic precipitators and 
combustion units are used for this purpose at the iron ore recovery plant, 
electrostatic precipitators at the nickel refinery, and packed water scrubbers at 
the three acid plants. 

Emissions from the 19^ m stack were not measured directly in the stack, 
but in the flues from the iron ore recovery, the nickel refinery and the acid 
plants. These flues were not readily amenable to stack sampling and the 
measurement methods had to be compromised and less rigorous procedures used 
because of limitations in locating suitable sampling sites. Consequently, the 
accuracy of measurements was affected and somewhat larger errors are 
associated with the reported emissions from the 19^ m stack. 

3,3.1 IRON ORE RECOVERY AND PELLETIZER PLANTS 

There are four processes involved in iron ore recovery at the Inco plant: 
roasting and reduction of pyrrhotite concentrate, leaching, recovery and 
pelletizing. The purpose of these processes is to recover nickel from pyrrhotite 
concentrate received from the Inco smelter and to prepare iron rich pellets for 
marketing. In the roasting step, most of the sulphur is eliminated by oxidation at 
high temperatures. Off-gases from six fluid bed roasters are cleaned of 
particulate materials and sent to the acid plants. These gases can be 
temporarily diverted to the 19^ m stack in case of upsets, however, if problems 
persist, the plant is shut down. To facilitate the separation of nickel from iron 



- la - 

in the subsequent leaching and reduction steps and to reduce the oxides of iron, 
the concentrate from the roasters is treated in six reduction kilns. Off-gases 
from six fluid bed roasters are cleaned of particulate materials and sent to the 
19^ m stack. It can be suggested on the basis of stack tests that the reduction 
kilns are a major source of particulates emitted from the 19^ m stack. Leaching 
and recovery plants are sources of ammonia emissions from small stacks on the 
building roof or process equipment vents -ammonia is used in the process of 
nickel recovery from the reduced concentrate. The concentrate, removed of 
nickel, copper and cobalt, is sent to the iron ore pelletizing plant to produce 
concentrate pellets rich in iron and suitable for marketing. In order to produce 
the pellets, the leached magnetite from the leaching plant is first dewatered to 
make filter cake, which is then dryed in two sintering machines. Gases from 
these machines are emitted via two ^5 m stacks and four small stacks on the 
building roof. The two t*5 m stacks were major sources of iron and total 
particulate emissions in the Basin until the plant shut down in April, 1980. 

3.3.2 NICKEL REFINERY 

Nickel sulphide from matte processing is further processed in the nickel 
refinery to make nickel in either powder or pellet forms. Nickel sulphide, 
precious metal intermediate products, and refinery residues are first briquetted 
and then oxidized in two converters. The finished metal is further processed to 
produce metallic granules which undergo carbonylation, purification, 
decomposition and either pelletization or powderization. The most significant 
source of emissions to the 194 m stack is the converting step. The gases 
exhausted from the converters are passed through electrostatic precipitators 
prior to entering the flue leading to the stack. Even though converting is a batch 
process operated intermittently, these two converters were the second largest 



- 15- 

source of nickel emissions in the Sudbury Basin up until 1980, when additional 
precipitation capacity on each converter was installed. 

3.3.3 SULPHURIC ACID PLANTS 

Inco also operates three sulphuric acid plants, adjacent to the iron ore 
recovery process from which they receive sulphur dioxide. The sulphuric acid 
process involves oxidation of sulphur dioxide on a catalyst to produce sulphur 
trioxide, and absorption of sulphur trioxide in absorption towers. Residual 
sulphur dioxide gas not converted to acid (conversion efficiency of about 93%) is 
vented to the atmosphere via the 19^ m stack. 

3A THE FALCQNBRIDGE 93 M STACK 

About 7100 standard cubic meters of gas at 120° - 160°C are emitted from 
this stack every minute. The stack receives off-gases from the Falconbridge 
smelter operations, which include smelting and converting, as well as the off- 
gases from the adjacent sulphuric acid plant. Prior to entering the stack, the 
process gases pass through an electrostatic precipitator for the removal of 
entrained particulates. 

The Falconbridge smelting process was changed in 1978, hence, the 
emissions from the plant should be considered in two periods: before and after 
this change. There were no satisfactory emission measurements performed on 
the old process and the only acceptable emission estimates up to 1978 are those 
of sulphur dioxide as calculated by mass balance. Emissions of some metals 
from the old process were also measured on two occasions, however, the 
accuracy of these measurements was judged unsatisfactory. Since 1978, two 
lines have been instcilled at the smelter, each containing a fluid bed roaster and 



- 16- 

an electric furnace, replacing the sintering machines and blast furnaces in the 
old process. The off-gases from the roasters are cleaned of particulates in 
cyclones and electrostatic precipitators, cooled, and sent to an acid plant for the 
conversion of sulphur dioxide to sulphuric acid. The solids from the roasters are 
fed to electric furnaces for smelting. Similarly to the roaster off-gases, 
emissions from the furnaces are first passed through cyclones and electrostatic 
precipitators and then sent to the stack. The furnace matte is sent to converters 
for further removal of iron and sulphur. There are four converters of which 
three are operated at any one time. The off-gases from the converters are sent 
to the electrostatic precipitators and then to the stack. 






- 17 - 

tt, DISCUSSION OF EMISSION MEASUREMENT METHODS, 
THEIR FREQUENCY AND ACCURACY 

The emission measurement methods applied at the Sudbury sources varied 
in complexity and accuracy, depending on the source and the manpower available 
for these measurements. They were, in most cases, either identical to or 
modified methods in the Ontario Source Testing Code (OSTC) (36). When 
modifications to the prescribed methods were made, it was either demonstrated 
that the measurement accuracy was not affected to a large degree or the 
construction limitations at the given sources were such that no other acceptable 
alternative existed at the time. In some cases, novel and unconventional 
methods, such as in-plume measurements, were applied. At most sources, 
measurements were done in one period of short duration and, consequently, the 
results reflect the emissions in effect during that period. 

At the largest Sudbury source, the Inco 381 m stack, the particulate 
emission measurements were done at least once a year in the period from 1973 
to 1980, producing relatively abundant emission data points. These emission data 
were correlated with the emissions of sulphur dioxide, thus enabling prediction of 
particulate emissions, within the given error margin, at any time, providing that 
either the production rates in the smelter or the emissions of sulphur dioxide 
from this stack are known. Emissions of sulphur dioxide from this stack are 
measured continuously with a continuous emission monitoring system, however, 
in the absence of measured values, these emissions could be calculated by mass 
balance. The continuous emission monitoring system at the 381 m stack was 
exhaustively examined and calibrated against a reference method in 1973, and it 
was then demonstrated that the system was accurate to within 10%. 



- 18- 

Me^lsurements of particulate pollutants at the 381 m stack in 1973 and 
197^ were done according to rigorous testing procedures, and the obtained 
results are believed to be the most accurate of all the emission data available 
for this stack. In 197^*, attempts were made to simplify testing procedures and 
special tests to compare so called one-point sampling with multi-point sampling 
techniques were carried out for the first time. Starting in 1975 only one-point 
sampling had been used at this source until 1980, when another simultaneous 
single-point and multi-point testing program was performed. These tests were 
designed to measure the magnitude of error associated with single-point 
sampling. The results suggested that single-point sampling could underestimate 
emissions by as much as 60% (22). A similar magnitude of error was indicated 
from the correlations between the emissions of particulates and sulphur dioxide 
from this stack, as discussed later in this report. 

Besides errors arising from single-point sampling, there were 
inconsistencies in the chemical treatment of particulate samples in different 
years, causing difficulties in comparing the measured yearly values. In order to 
remove these difficulties and, at the same time, to conform to the definition of 
particulate matter as given in the OSTC, sulphates and free sulphuric acid found 
prior to and on the filters of the sampling trains after the tests were considered 
particulates and were included in the calculation of particulate emissions. This 
still did not eliminate all inconsistencies, particularly those due to different 
distribution of acid in the sampling trains caused by different filter temperatures 
during samplings, but it helped to obtain better correlations between the yearly 
results. 

Measurements of sulphuric acid emissions from most of the Sudbury 
sources are difficult due to limitations of the sampling method. The method 
used in the measurements is known as the U.S. E.P.A. Method 6 (37), which is 



- 19- 

directly applicable to sulphuric acid plants, but had to be modified for the other 
sources in Sudbury. These modifications were not always successful, and 
difficulties were met when trying to separate sulphates from free acid during 
sampling and to distinguish between these two species in subsequent chemical 
analyses. Selective chemical extractions and elevated temperatures of the 
probes and filters of the sampling trains during sampling applied in latter years 
helped, but did not completely resolve the problem. In some tests, the solvent 
used for the extractions was not completely selective because of impurities, and 
the sampling temperatures were not maintained sufficiently high because of 
sampling equipment limitations. 

Sulphur dioxide is another possible interference in the acid emission 
measurements. It can be either oxidized under favourable conditions to form 
sulphuric acid or retained in the impinger solutions to interfere in the chemical 
analysis. While both of these mechanisms can be controlled by careful 
preparation and execution of sampling, it is possible that in the actual 
measurements this was not always achieved, and that the sulphuric acid results 
from some tests are biased. 

Emission measurements of most trace metals were more accurate than 
either particulate or acid measurements. Error in these measurements were due 
to single-point sampling and the chemical analyses of the samples. The only 
exceptions are volatile metcils such as mercury, arsenic, and selenium, which 
were determined accurately on one occasion at the 381 m stack by using a 
specially designed emission measurement method in 1980. 

Emission measurements at the Falconbridge stack and the Inco 19^ m stack 
were also difficult due to problems similar to sampling at the 381 m stack: 
traversing of stacks and flues was incomplete due to practical limitations and 



- 20- 

sarnples of particulates and sulphuric acid were subject to similar interferences. 
These problems are fully described in the discussions of emissions of individual 
species from these sources. 

Mass balance was used to estimate sulphur dioxide emissions, whenever 
FKJSsible, and these estimates can be considered accurate to within 10%, as will 
be discussed later. 

Ammonia emissions from Inco's iron ore recovery plant were estimated by 
mass balance, based on measurements related to chemical makeup, liquid 
effluent loss, and specific process emission vent losses, with the remaining 
unaccounted losses included as part of atmospheric emission loss (24). 

The low level emissions from the Inco smelter building as given in the 
original testing reports prepared by the company (12, 14, 17, 20, 21) are probably 
the least accurate of the emission data presented in this report. This was due to 
difficulties in sampling, which are typical in fugitive emission measurements, for 
the following reasons: emissions are intermittent in both strength and duration; 
sampling areas are large, with uneven gas flow and occassionally low gas 
velocities; problems are experienced in locating "representative sampling 
points*'; there are difficulties in assigning a portion of unconfined and wandering 
emissions to a specific process unit within the building; and, commercially 
available sampling equipment is not suitable for these measurements and special 
sampling trains have to be built. Low level emission measurements at Inco's 
smelter were done on a process unit basis, where a reverberatory furnace, a 
nickel converter, a multiple hearth roaster, the copper flash furnace and a 
copper converter were selected as representative of other corresponding process 
units in the building, and the measured emissions prorated to include all process 



- 21 - 

units. Measurement errors eissociated with individual process units are given in 
the testing reports and they were used to calculate the total error in the 
reported low level sulphur dioxide emissions from the smelter. This error was 
+27% (33). The error in particulate emissions was not estimated, but it is 
expected to be larger than in the case of sulphur dioxide because of possible 
stratification effects on sampling accuracy. 

The size of emitted particulates from the stacks was measured by 
impaction techniques and generally these measurements are considered accurate. 
When there were doubts about the execution of some tests, the tests were 
repeated and unreliable results discarded. 

In-plume measurements were also attempted as a substitute for in-stack 
emission measurements. Sometimes the results from the two methods were 
fairly similar, however, on occasion the differences were large and impossible to 
explain. In these cases it was assumed that the in-stack method was more 
accurate. 



- 22- 
5. SULPHUR DIOXIDE EMISSIONS 

Yearly sulphur dioxide emissions from most smelting processes could be 
conveniently calculated by a mass balance procedure. However, difficulties and 
inaccuracies could arise, if the emission data from more than one stack which 
receive off-gases from the same process are required. In these situations, 
sulphur dioxide measurements at each stack is the only viable alternative. 
Measurements will also produce more accurate emissions over shorter periods, 
e.g. days or weeks, when inaccuracies in process sampling and weighing of the 
process streams required for mass balance could have a more significant effect 
on the accuracy of emission calculations. 

A combination of measurements and mass balance was used to produce 
sulphur dioxide emissions from the major industrial sources in the Sudbury Basin 
as shown in Tables 1 and 2. Emissions from the Inco 381 m stack are mass 
balance values as reported by the company and they agree with the yearly 
average of the measured values to within 1-2%. Since the measured values were 
shown to be accurate to within 10% (1), it is likely that the mass balance values 
in Table 2 are at least as accurate. As far as other emissions in Table 2 are 
concerned, the Falconbridge and Inco 19^ m stack data were obtained by mass 
balance, while the Inco smelter low level emissions were measured in 1978 and 
1979, and prorated to other years on the basis of production. 

For Inco, shutdowns and/or labour strikes in 1978 and 1979 were responsible 
for lower emissions in the Basin in those years. Sulphur dioxide emissions for 
1980 and 1981 from the Inco 381 m stack reflect more stringent emission 
requirements imposed by the Ministry in 1980 which were met as a result of 
reduced production. With respect to emissions from the Falconbridge smelter, 
the levels were reduced as of 1978 largely due to process changes (installation of 



-23- 

fluid bed roasting - electric furnace smelting - sulphuric acid manufacturing). 
However, summer vacation shutdowns and lower production levels also 
contributed to the lower emissions presented in Table 2. In other respects, the 
tabulated emissions should be regarded as representative of each source. The 
measurement methods, correspondence between emissions and production as well 
as the accuracy of prorated emissions given in Table 2 are discussed for each 
source separately. 



TABLE 2: YEARLY EMISSIONS OF SULPHUR DIOXIDE FROM MAJOR 
INDUSTRIAL SOURCES IN THE SUDBURY BASIN IN THOUSAND TONNES 



Year 


Inco 381 m 


Inco Low Level 


Inco 194 m 


Falconbridge 




Stack* 


Smelter** 


Stack* 


93 m 
Stack* 


1973 


1,171 


14 


104 


274 


197^ 


1,126 


16 


74 


258 


1975 


1,1^1 


m 


40 


195 


1976 


1,163 


13 


41 


191 


1977 


1,069 


13 


52(55***) 


200 


1978 


535 


& 


24 


117 


1979 


383 


i 


19 


88 


1980 


733 


It 


66 


123 


1981 


650 


9 


64 


114 


Average 


885 


12 


54 


173 


96 of total 


78 


1 


5 


16 



Determined by mass balance Ccilculations 
** Determined from measurements in 1978 and 1979 and prorated to other 

years on the basis of production, 
*** Determined from stack measurements. 



5.1 THE INCO 381 M STACK 



With 7896 contribution to the total emissions of sulphur dioxide in the 
Sudbury Basin, the 381 m stack is the largest single emitter of sulphur dioxide in 
the area. The accuracy of total sulphur dioxide emissions from the Basin 
depends to a large extent on the accuracy of these 381 m stack emissions, and it 
is for this reason that they have been measured on a continuous basis since 1973, 



in 

:o 
m 

in 



in 
in 



□ 



m 
in 



7I.M 



n. 



II. 



7I.M 







" T i S i i i I * ^ ^ ^ ^ *■ ^ * ^ 

B B P ■ i i B R n r B B P ■ R n 
E5TIMRTED 5D2 EM 1 55 1 DN BY MR55 BHLRNCE ( TDNNE5/H ) 

FIGURE 2. SULPHUR DIDXIDE EM1551DN5 CDMPUTED BY MR55 BRLRNCE 

V5 EM 1 55 I DNS MER5URED RT THE INCD 3B I M 5TRCK 



- 25- 

The continuous emission monitoring installation for sulphur dioxide was verified 
through extensive testing in 1973, when it was demonstrated that the system was 
accurate to within + \0%. The measured emissions were also compared with the 
available computational estimates by mass balance in 1973 and 197^, and a 
relationship between these two sets of results is shown in Figure 2, 

The plotted line in Figure 2 represents an ideal one-to-one relationship, 
assuming no error by either method. The measured values are spread around this 
line with the largest individual point deviation being about 30%, which, 
considering that both the continuous monitoring and short term mass balance 
methods are susceptible to errors, should not be unexpected. Figure 2 still 
illustrates that the two methods are essentially equivalent over longer time 
periods. This equivalency has also been confirmed in Inco's progress reports on 
continuous monitoring, which indicate that yearly values obtained by the two 
methods agree to within 2%, while monthly averages may differ by as much as 
16% (32). 

The available measured emissions were also plotted against the total ore 
concentrate input to the roasters and the total feed to the nickel converters in 
Figures 3 and ^, respectively. Straight best fit lines shown in these figures were 
calculated by the least squares method. 

The large scatter of points about the lines in Figures 3 and ^ may be a 
result of the variable sulphur content of the feeds to both the roasting and 
converting operations. More uniform sulphur content of the reverb matte fed to 
the converters resulted in better correlation and smaller scatter in Figure ^, 
From these figures, it is calculated that, depending on feed rate, sulphur dioxide 
emissions range from 0.66 to 0,78 tonnes for every tonne of the total material 
input into the converters and from 0.61 to 0.8^ tonnes for every tonne of the ore 
concentrate fed into the roasters. 



m 
m 
in 

CD 

m 



m 
in 



m 
Ln 



in. 

171. 
IB. 

in. 
\m. 
m. 
la. 
111. 
in. 



Ti.n 
n.u 






+ 




OS 



+ 



1— T—f 



n n 



R 



B 



* 



t 

i 



i-nr—r- T 



FIGURE 3 



--------ISHBI? 

RDH5TER MRTERIflL INPUT ( TDNNE5/H ) 

SULPHUR DIDXIDE EMI5S1DN5 V5 RDR5TER MRTERIRL INPUT 



:□ 
in 

:a 
m 
c» 

m 
t=i 
r»j 

m 



in 
in 



□ 



m 
in 



71 



II 



71 



»•■% 



B 



+ 



+ 



+ 



+ 



+ + 



+ 



IS 






1 i 1 f 



i 



81 



•3 



t 

ki 



t 



CDNVERTER MBTTE INPUT ( TDNNE5/H ) 

FIGURE H. SULPHUR DIDXiDE EMISBIDNB V5 CONVERTER MRTTE INPUT 



-28- 

The significance of the relationships between the process material flows 
and sulphur dioxide emissions is that they illustrate a proportionality between 
these two parameters and enable use of either of them as an indicator of 
production activity in the smelter. However, a caution should be exercised 
because the correlations as calculated from Figures 3 and ^ may have changed 
since 1973, as a result of process changes, but these changes are not expected to 
alter the fact that the sulphur dioxide emissions are directly proportional to 
production. 

5.2 INCQ LOW LEVEL EMISSIONS 

The low level emissions from the Copper Cliff smelter building were 
measured by Inco personnel in a series of tests at various vents, windows, and 
small stacks on the roof of the building. No similar measurements were done at 
the other Inco buildings or the Falconbridge smelter. The tests at Inco were 
specially designed and executed such that the measured emissions from the 
single process units selected for measurements as representative of a number of 
similar units in the same building were used to calculate the total emissions from 
the building. The origin of these emissions was already discussed in general 
terms in the process description; however, for more details, reference should be 
made to the relevant Inco reports (12, 14, 17, 20, 21). Emissions shown in Table 
2 were prorated to average yearly production rates of bessemer matte and 
blister copper. Difficulties encountered in these measurements as well as some 
estimates of associated measurement errors are given in the Inco reports listed 
above. From these error estimates, it was calculated that the total low level 
emissions of sulphur dioxide shown in Tables 1 and 2 should be accurate to 
within + 27% (33). 

From among the individual processes, the largest contributor to these low 



-29- 

level emissions of sulphur dioxide are the reverberatory furnaces which account 
for about ^2% of the total low level sulphur dioxide emissions, followed by the 
converters at 38%, the copper flash furnace at 19% and the roasters at 1% (21). 
From another Inco report (27), the contributions to the total emissions for the 
copper converters are ^1%, followed by the nickel reverberatory furnaces at 
25%, the copper flash furnace at 17%, the nickel converters at 8% and 
miscellaneous sources at 9%, 



5.3 THE INCO 19^ METRE STACK 

The flues from Inco's nickel refinery, the sulphur products plant and the 
iron ore recovery plant are joined to the 19^ m stack. Because of the 
unavailability of suitable sampling platforms at the stack, all emission 
measurements were carried out at the three flues that convey the emissions 
from the individual plants to the stack. Sulphur dioxide emissions and the 
corresponding production rates, as given in the emission testing reports (8, 9, iO), 
are shown in Table 3. 

Sulphur dioxide emissions in Table 3 are based on the results of several 
tests of limited duration carried out when the production rates were as 
indicated. Only in the case of the nickel refinery were the emissions prorated to 
correspond to a typical production rate in 1977. These nickel refinery emissions 
are intermittent, and the result in Table 3 corresponds to approximately three 
"converter heats" per day, each heat lasting about four and a half hours. The 
emissions during the heat changed from a low of 5% to a high of 60% of the total 
for the heat. Emissions from the sulphuric acid plant are continuous and also 
dependent on production. The sulphuric acid production rate shown in Table 3 is 
somewhat less than the maximum rated capacity of 2721 tonnes per day. 



- 30- 

Emissions from the iron ore recovery plant are continuous and subject to 
fluctuations. The fluctuations were so large during testing that some doubts 
about the validity of tests and the meaning of the obtained results were 
expressed (29). Fortunately, this plant is the least significant contributor of 
sulphur dioxide emissions to the 19^ m stack, and any error in these 
measurements will not affect significantly the accuracy of the total emissions 
from the stack. 

All emissions from individual flues were measured instrumentally, and in 
the case of the nickel refinery, they were compared with mass balances 
calculated over both short and long time periods (9). The agreement between the 
measurements and long-period calculation was excellent, while short period mass 
balance indicated about 62% lower emissions. 



TABLE 3: SULPHUR DIOXIDE EMISSIONS FROM INDIVIDUAL PROCESSES 
TO THE INCO 19^!^ METRE STACK IN TONNES/DAY IN 1977. 



Source 


Sulphur Dioxide 
Emissions 


Production Rate 


Sulphuric Acid Plants 
Nickel Refinery Plant 
Iron Ore Recovery Plant 


91.9 
^8.2 
9.* 


2300 tonnes/day of 
sulphuric acid 

21^.2 tonnes/ day of 
dry charge to refinery 

2267 tonnes/day of 
roaster feed 


Total 


1^9.5 





- 31 - 
5A THE FALCQNBRIDGE 93 M STACK 

This stack is the second largest sulphur dioxide emitter in the Sudbury 
Basin, contributing on average about 16% of the total over the nine year period, 
as indicated in Table 2. These emissions have been computed by mass balance 
and reported by the company (13). In 1979, they were also measured over a short 
period, and the measured emissions were compared with the meiss balance values. 
The comparison was not successful in that the measurements indicated about 
^9% higher emissions, probably as a result of errors in both the measurement and 
short term mass balance. However, the values in Table 3 should still be 
considered as an accurate representation of the emissions from this stack. The 
Falconbridge plant emissions are variable due to a batchwise operation of the 
converters and possibly variable efficiencies of the sulphuric acid plant, which 
both release off-gases to the 93 m stack. 



- 32- 
6. EMISSIONS AND SIZE OF TOTAL PARTICULATES 

Total particulates are the second most significant pollutant emitted from 
the industrial sources in the Sudbury Basin. However, in comparison to sulphur 
dioxide, the particulate emissions amount to only about 1.8% of the sulphur 
dioxide emissions. 

Similarly to sulphur dioxide, most of the particulate emissions in the basin 
are due to Inco's 381 m stack. The 381 stack emissions, as shown in Tables 1 and 
i^t were obtained from a linear correlation between the particulate and sulphur 
dioxide emissions measured in the period from 1973 to 1980 such that they 
correspond to yearly emissions of sulphur dioxide. Since the sulphur dioxide 
emissions depend on the production rates in the smelter, the estimated 
particulate emissions are indirectly normalized with respect to production and 
represent the best available average particulate emissions from this source. 
Since about 75% of the total particulate emissions in the Sudbury Basin are due 
to the 381 m stack, any variation in these emissions will have a significant effect 
on the overall emissions of total particulates as well as of the other particulate 
pollutants in the Basin. 

The low level particulate emissions as shown in Table fi- were also 
normalized with respect to production; however, in this case only one set of 
measured values from Inco's 1978-1979 testing program was available. 
Consequently, the calculated emissions shown in the table are less accurate then 
those for the 381 m stack. No such normalization was done for any other source 
listed in Table 4, and the indicated emissions from these sources were measured 
in only one set of tests. Emissions from the two ^^5 m smokestacks ceased in 



- 33- 

April 1980, when the pellet plant was shut down (25). Emissions from the Inco 
19^ m stack have also been reduced since 1980, when additional precipitators 
were installed at the nickel refinery flues. Presently, no satisfactory stack test 
data are available for the estimation of this reduction. 



TABLE ^: YEARLY EMISSIONS OF TOTAL PARTICULATES IN TONNES 

FROM MAJOR SOURCES IN THE SUDBURY BASIN 

FROM 1973 TO 1981. 



Year 


Inco 381 m 


Inco Smelter Low 


Inco 194 m 

and two 45 m 


Falconbridge 
93 m 




Stack 


Level Emission 


Stacks 


Stack 


1973 


12,166 


650 






1974 


1^,144 


730 






1975 


14,299 


155 






1976 


14,494 


721 






1977 


13,763 


703 


2,380** 




1978 


8,057 


387 






1979 


6,491 


283 


4,064* 


865 


1980 


10,096 


548 






1981 


9,241 


497 






Average 


11,417 


586 






Standard 


Sxy=4,588 


Error of 










Estimate 











* Emissions from two 45 m stacks not applicable after April 1980, due to 

plant shutdown. 
** These emissions were decreased in 1980 as a result of additional 

precipitator capacity at the nickel refinery plant flues. 



6.1 THE INCO 381 M STACK 



Emissions of total particulates from the 381 m stack were measured in at 
least one short period every year from 1973 - 1980, The average results of these 
measurements are shown in Table 5. They were based on: one test in 1975, two 
tests in each of 1976, 1978, and 1980, four tests in each of 1974 and 1977, six 



- 3^*- 

tests in 1973 and 16 tests in 1979. Other tests that could have been done in any 
of these years were excluded because of a lack of detailed data on the chemical 
composition of the samples. Since the number of tests, the time periods of 
testing, and the production rates differed in each of these years, the emissions in 
Table 5 cannot be compared directly with each other or considered as 
representative of yearly emissions. Also, they are not identical to the emissions 
given in the original test reports because of the inclusion of the condensed acid 
in the particulate emissions. This inclusion was done to enable a direct 
comparison of emissions measured in different years and to conform with the 
definitions in the provincial testing code. In earlier reports, the original 
emissions included the part of sulphuric acid which was condensed at the 
sampling temperatures while the particulate emissions in later reports were 
completely free of this acid (different chemical treatments of particulate 
samples in different years were responsible for these inconsistencies). In the 
1973 and 197^ tests, particulate samples were extracted with acetone which 
removed some of the acid, and these partially acid-free particulates were used 
to calculate the particulate emissions. Starting in 1975, isopropanol replaced 
acetone because of its effectiveness as a selective extractive chemical for the 
free acid and, consequently, the emissions after 1975 did not contain any free 
sulphuric acid. In order to make all emissions measured at this stack 
comparable, the condensed acid, which at the sampling temperatures had been 
collected as a particulate, was included in the particulate emissions. In doing so, 
these emissions also conformed with the definition of particulates given in the 
provincial testing code (OSTC). Additional benefit was a slightly better 
predictability of particulate emissions from the knowledge of production and 
emissions of sulphur dioxide. 

The individual particulate emission results which were used to obtain the 
average emissions shown in Table 5 and the sulphur dioxide emissions measured 



- 35- 

simultaneously with the corresponding particulate tests were plotted and are 
shown along with a best-fit line in Figure 5. A plot of associated frequency 
distribution of errors in tonnes per hour is shown in Figure 6. 



TABLE 5: MEASURED AVERAGE PARTICULATE EMISSIONS FROM THE 
INCO 381 m STACK IN TONNES/HOUR 





1973 


197^ 


1975 


1976 


1977 


1978 


1979 


! , 
1980 


Emissions in 
Tonnes/ h 


2.U 


1.96 


2.32 


^.n 


1.50 


i.^i^ 


0.89 


1.57 


Standard 
deviation 
in Tonnes/ h 


0.359 


0.567 


- 


0.198 


0.212 


0.170 


0.255 


0.099 



The broken lines in Figure 5 indicate the limits in the standard error of 
estimate associated with the prediction of particulate emissions from this 
straight line relationship. Figure 6 illustrates that the points are scattered 
around the straight line in a random fashion, suggesting normal distribution of 
errors. These errors are compounded and consist of measurement errors and 
random process variations which could cause different relationships between the 
emissions of these two pollutants. Measurement errors alone could account for 
as much as 7^^ of the total error of which 10% could be due to sulphur dioxide 
determination and 6096 to particulate measurements, as discussed earlier. 



Despite the errors, or large scatter of individual measurements in Figure 5, 
this straight-line relationship can be used to either estimate particulate 
emissions from the knowledge of sulphur dioxide emissions or to assess the 
process operation when emissions of both pollutants are known. In case the two 
emissions fall outside the area enclosed by the broken lines in Figure 5, a 
significant change in the process operation could be suspected. 



- 36- 

Some of the emission data used in calculating the straight-line relationship 
in Figure 5 were obtained shortly after improvements to the electrostatic 
precipitators had been made, hence, the effects of these improvements on the 
particulate emissions are included in the relationship (31). These effects are also 
responsible for the largeness of scatter in Figure 5. In an attempt to further 
explain this scatter, residuals (difference between the measured and predicted 
value) from Figure 5 were plotted against years. This plot suggested that a 
significant drop in emissions may have occurred in 1976; and since the emissions 
were already normalized for production, this drop could not have resulted from 
lower production activities in the smelter. Since 1976 the normalized emissions 
have been steadily increasing until 1980, when they may have been only about 
10-20% lower then in 1973. 

The straight line relationship in Figure 5 was used to calculate the annual 
emissions of particulates in the period from 1973 to 1981 from the knowledge of 
the annual sulphur dioxide emissions (3^*). In Table 4, the calculated annual 
particulate emissions and the standard error of estimate are given. The 
calculated emissions are different from the measurement averages shown in 
Table 5 because of differences between the production rates during tests and the 
annual production rates. As a result, the calculated average emissions over the 
eight year period from 1973 to 1980 are smaller and amount to only about 83% of 
the average measured values in the same eight year period. 



6.2 THE INCQ 194 M STACK 

This stack is the second largest industrial source of particulate emissions in 
the Basin. From among the three groups of plants contributing to 






a.Bh 



r-1 Z.Oif 



ID 

—I 
m 



m 

in i.sBt 



E(PRRTI<:ULRTE) ^ E(BD2) X 0.0103 + 0.2907 
CDRRELRTIDN COEFFICIENT = 0.S3 
5TBNDHRD ERROR DP ESTiMRTE (5X/Y ) + 
= ± . 5:237 



+ 




I 

I 



■•"r-r-rr-ii-r-t 



AAAAAAAAAAA 



SRNfRB^BBiBSRRSiQBISBR 



5D2 EM IBS I DN ( TDNNE5/H ) 



FIGURE S. TQTRL PRRTKULRTE V5 SULPHUR DIDXIDE EM I 5B 1 DN5 



5Nai55m3 3<]ixai<] ynHdins ba 
3iBin:>iiyHd bua smahi jd NDiinaiyisK] A3N3nH3yj 



a lamiA 







ZQ5 5A 'Lm6 



rfl— rJ 



E'Z 



L'S Z 



B'B E 



h'tt h 



E'M 



5 



rii a 



B'BZ L 



G'ZZ B 



H3)U 
"OB f 



5iNna:> 



-39- 

the emissions from this stack, the acid plants are the least significant 
contributors of particulates, accounting for about 8% of the total emissions, 
followed by the nickel refinery with 36% and the I.O.R.P. with 56%. The 
average particulate emissions as measured in 1976, the corresponding production 
rates, and the particulate emission factors are shown in Table 6. 

Comments on the continuity of emissions from the iron ore recovery plant 
(I.O.R.P.) and the three acid plants, their intermittency from the nickel refinery 
plant, and on the production in the plants given in the discussion of sulphur 
dioxide emissions are also applicable to emissions of particulates. The nickel 
refinery is an intermittent source and its daily emissions as shown in Table 5 
cannot be divided by 2^ to obtain the actual hourly emissions since the hourly 
emissions fluctuate depending on number of heats performed in the day and heat 
cycle. The emissions in Table 5 represent the total from three heats a day, each 
heat of four and a half hours duration. 



TABLE 6: PARTICULATE EMISSIONS FROM THE INCO 19^ M 
STACK IN TONNES/DAY 



Source 


Particulate 
Emissions 


Production 


Emission 
Factor^ 


I.O.R.P. 

Sulphuric Acid Plants 

Nickel Refinery 


3.36 

0.^8 
2.68+ 


2310 tonnes*/day 
2308 tonnes* */day 
3.06 heats»**/day 


1.5 kg/ tonne 
0.2 kg/tonne 
0.9 tonne/heat 


Total 


6.52+ 







* Tonnes of sulphuric acid 
** Tonnes of pyrrhotite 

* ** Heats of converters 

o Particulate Emissions/Production 

* Emissions applicable up to 1980. 
installed in 1980. 



More electrostatic precipitators 



-40- 

As far as the accuracy of measurements are concerned, problems were 
experienced in sampling at both the I.O.R.P. and the nickel refinery plant due to 
nonideal measurement locations and partial traversing within the horizontal 
flues. Consequently, the particulate samples collected in these measurements 
may not be representative of the particulates emitted from these plants. No 
specific tests were performed at either plant to provide the data required for the 
estimation of measurement errors, however, these errors could be expected to be 
larger than the 60% estimated for the 381 m stack. 

Particulate emissions from the nickel refinery plant were decreased in 
1980 after the installation of additional precipitators in the two converter flues 
(30). However, no satisfactory emission testing data are presently available to 
either assess the degree of improvement or to quantify the emissions of 
particulate pollutants from the new process. 

The acid plant emissions in Table 6 include the portion of sulphuric acid 
which was condensed at the sampling tempjerature, in accordance with the 
discussion of particulate emissions from the 381 m stack. No such corrections 
were applied to the emissions from the other two plants because the data on the 
condensed portion of the acid was not available.. 



6,3 THE FALCONBRIDGE 93 M STACK 

Particulate emissions from the 93 m stack were measured in 1973 and 
1979. The results from 1973 are the only available emission data applicable to 
the old process at the Falconbridge plant and they suggest fairly high emissions 
at 19,2 tonnes per day. Unfortunately, since these measurements were done at 
only one point of the stack cross-section cind were short in duration, their 
accuracy cannot be considered satisfactory. 



- 1*1 - 

A more detailed measurement program was executed in 1979, when the 
new process was on line. The measured emissions were much lower at 2.37 
tonnes per day. The error associated with these measurements was estimated at 
about + 38%. These emissions were recalculated to include the condensed 
portion of sulphuric acid. 

During the emission measurements, the average feed rate to the roasters 
was equivalent to 1,703 tonnes per day. The particulate emission factor based 
on this roaster feed is 1,^ kg of particulates for each tonne of the roaster feed. 



G.it INCO'S LOW LEVEL EMISSIONS 

The relative contribution of this source to the total particulate emissions 
from the Basin is surprisingly larger than in the case of sulphur dioxide 
emissions. The low level particulate emissions at 1.6 tonnes per day account for 
about 3.9% of the total particulate emissions in the Basin, while a similar 
percentage for sulphur dioxide is about 1.1%. It is not known whether this is a 
result of measurement errors or a reflection of the actual relationship between 
these two pollutants in low level emissions. As was already indicated in the 
description of processes and measurement methods, the measurement of low 
level emissions was a difficult and complex task, which required development of 
special methods. These methods were at times crude and unproven. For 
example, in one case, visual observation was used to assign a relative 
contribution factor to the emissions sampled in a ventilator for each of the two 
adjacent process units. This factor was then used to calculate emissions from 
similar units. In other instances, particulate emissions were sampled in large 
ventilators over long time periods, using methods which had to be simplified in 
order to make them practical. While these simplications may have a less 



-^2- 

significant effect on the accuracy of measurements of gaseous species, e.g. 
sulphur dioxide, they could cause larger errors in the case of particulates. 
Hence, it should not be surprising if the measurement error in some tests was 
even greater than + 60% as reported by the Inco's smelter process technology 
group (1^). 

From among individual smelting processes, the largest contributor to the 
low level particulate emissions from the smelter are the copper converters, 
accounting for 6^-70% of the total, followed by the multiple hearth roasters with 
9-11%, the reverberatory furnaces with 9-11%, the nickel converters with 9-11% 
and the copper flash furnace with 3% (21,27). Emissions from each of these 
processes were prorated to include production in all units in the smelter and so 
prorated emissions are shown in Tcible 4 (38). 



6.5 SIZE OF EMITTED PARTICULATES 

Emissions from all processes in consideration are cleaned from a bulk of 
pollutants, particularly those in particulate form, prior to entering the stacks. 
Electrostatic precipitators are used in the majority of the plants, except at the 
sulphuric acid plants where water scrubbers are used. These precipitators are 
particularly effective in removing particulates of large size, thereby leaving in 
the emissions mostly particulates with aerodynamic diameters of less than 10 to 
15 urn. These small particulates could be airborne and respirable, and, therefore, 
it is important to characterize them in terms of size and chemical composition. 

Commonly used parameters in particle size characterization are the 
aerodynamic diameters (DP) of the given weight fractions of the particulate 



- ^3- 

sample. Thus DP 50% of 5 um means that, in terms of weight, 50% of all 
emitted particles have aerodynamic diameters equal to or less than 5 urn. In 
addition to DP 50% or mass median diameter (MMD), cut-off diameters of 15.9% 
and 84.1% weight fractions of the sample are usually reported, to enable a more 
complete characterization of the size distribution, Impactor methods, which are 
frequently used in the size measurements, do not always distinguish between 
particles larger than about 10 to 15 urn. In order to obtain the size information 
in this range, the measured data must be extrapolated, which in turn may 
accentuate small measurement errors to quite large differences in the 
extrapolated results. This source of error must be recognized when interpreting 
the sizing data. 

Particulate sizes were measured at the Inco 381 m stack on several 
occasions and at the Falconbridge's 93 m stack once. No measurements were 
performed at the other sources. Both in-stack and in-plume measurements were 
carried out at both of these stacks. 



6.5.1 PARTICULATE SIZE MEASUREMENTS AT THE INCO 381 M STACK 

The in-stack particulate size measurements at the 381 m stack were done 
over the period of eight years, and the results of these measurements are given 
in Table 7. 

The available test data from 1973 do not contain the weights of large particles 
retained in the inlet portions of the impactor samplers, resulting in too small 
mass median diameters, as shown in Table 7. However, if the data from 1976 are 
truncated to exclude the inlet portions of the samples, the mass median 



- ^^- 



TABLE 7: SUMMARY OF PARTICLE SIZE MEASUREMENTS AT 
THE INCO 381 M STACK 



Year 


No of Tests 


DP 50% 


Dp 15.9% 


DP 8^.1% 


% of Sample 






um 


um 


pm 


included 


1973* 


2 


1.9- 2.9* 






50% 


1976 


3 


6.8 - 7 A 


0.9 - 1.3 


16 - 1*7 


100% 


1977 


1 


8 


1.2 


^8 


100% 


1978 


3 


3.5 - 5.5 


0.65 - 0.89 


19 - 36 


100% 


1980 


3 


3.3 - G.ii 


0.53 - 0.72 


23 - 60 


100% 



* Incomplete sample yielding a nonrepresentative result. 



diameters of the truncated samples are comparable to those from the 1973 
program. This suggests that the size of particulates in 1973 and 1976 may have 
been similar. The particulate size distributions in 1976 and 1977 were also 
similar. Tests in 1978 and 1980 resulted in slightly smaller particulates. 
Measurements in 1978 were particularly exhaustive, and the results from that 
year can be considered accurate and representative of emissions from this stack 
(18). 



6.5.2 PARTICULATE SIZE MEASUREMENT AT THE FALCONBRIDGE 93 M STACK 



The size measurement tests at this source were performed in 1979, and the 
particulates were found to be somewhat smaller than in the Inco 381 m stack. 
Since similar measurement methods were used at both sources, the differences in 
the results must be attributed to processes and process equipment, including the 
electrostatic precipitators at the two smelters. The results obtained at the 
Falconbridge stack are given in Table 8. 



- ii^ - 



TABLE 8: SIZE OF PARTICULATES EMITTED FROM 
THE FALCONBRIDGE 93 M STACK 



No of Tests 



DP 50% 
2.3- 4 



DP 15.9% 
um 

OAH - 0.66 



DP 8^.1% 
um 



10- 33 



% of Sample 
Included 



100% 



In-plume measurements were also carried out at Faiconbridge, and no 
significant diftcrences between the in-plume and in-stack size measurement 
results for most metals of interest were recorded (19, 23). 



- ^6- 
7. EMISSIONS OF METALS 

Emissions of metals in the Sudbury Basin follow the trend established for 
particulates, thus, on the average the largest source of nickel, lead and arsenic 
emissions is the Inco 381 m stack, followed by the Inco 19^ m stack, the 
Falconbridge 93 m stack, and Inco's Copper Cliff smelter building. However, in 
terms of particulate composition, the 194 m stack is by far the most significant 
source of copper and nickel. Even in terms of absolute quantities, this source 
used to emit almost as much of these two metals as the 381 m stack prior to 
installation of additional precipitation capacity at the nickel refinery in 1980. 
(No satisfactory emission data applicable to the present operation at the refinery 
are available). Another significant source of copper is Inco's Copper Cliff 
smelter building, contributing about 37% of all copper emissions in the Basin. 
Iron was mainly emitted from Inco's two 45 m stacks until the pellet plant 
shutdown in 1980. 

Not all metals were determined in all emission measurements for the 
Sudbury sources, however, the major species which, on the average, exceeded 
both one percent content of total particulate and the emission rate of 10 kg/h 
from the 381 m stack over the eight year period from 1973 to 1980, were 
quantified at all sources, and their emissions are listed in Table 9. 

The iron, copF)er, and nickel emissions from the 381 m stack were calculated 
from correlations with sulphur dioxide, while lead and arsenic emissions were 
averaged from three or more valid emission measurement tests. Emissions of 
metals other than those in Table 9, including cobalt, selenium, mercury, 
chromium, manganese etc., accounted for less than 1% of particulate emissions, 
as discussed under individual sources. 



-47- 



TABLE 9: AVERAGE EMISSIONS OF METALS FROM MAJOR 
SUDBURY SOURCES IN KILOGRAMS/HOUR 



Source 


Iron 


Copper 


Nickel 


Lead 


Arsenic 


Total 


Percent 
of Cont- 
ribution 


Inco 3Si m 
Stack 


113 
Sx,ysl09.5» 


28 
5x,y=19.8* 


26 
Sx,y=16.'^* 


21 
a=8.6»* 


13 

a=5.5»* 


201 


53.5 


Inco 19'» m 
Stack" 


73 


19.5 


26.2 


0.7 


0.4 


119.8 


31.9 


Inco smelter 
building low 
level 


8 


28 


3.5 


0.1 


0.01 


39.6 


10.5 


Falconbridge 93 m 
Stack 


u 


1 


1 


1.5 


0.8 


15.3 


UA 


Inco two i^i m 
Stacks 


(268.8)* 














Total° 


205 


76.5 


56.7 


23.3 


[t*.2 


375.7 





* • 

o 



Sx,y = standard error of estimate 

(T = standard deviation 

Emissions measured in 1977, inapplicable after the installation of new electrostatic 

precipitators at the nickel refinery in 1980. 

Emissions inapplicable after the pellet plant shutdown in 1980. Excluded from the total. 



Metals were analysed in almost every sample collected in the course of 
particulate emission measurements at all Sudbury sources- Analyses were 
frequently performed by at least two laboratories, Falconbridge's or Inco's and 
the Ministry of the Environment's. In the first sampling campaign at the 381 m 
stack, a third independent laboratory was engaged to analyse selected samples 
for cross-checking purposes. This was justified on the basis of uncertainties and 
novelties involved in early analytical work; however, when the proper procedures 
were well established and the approximate levels of metals in the emissions 
became known, the number of laboratories involved in any given measurement 
program was decreased. The number of metals analysed in particulate samples 
was also decreased to include only major constituents. 



Some metals of interest, mercury, arsenic, lead and selenium, are volatile 
and their collection in the sampling stage was not always assured. Thus, if the 
particulate sample was analysed for any of these four species with no 
modification in the sampling procedure to ensure their quantitative collection, 
the obtained results were in error and inconsistent with expectations. In the 
case of the 381 m stack, these uncertainties were removed by performing 
specially designed emission tests in 1980, and this program resulted in the most 
reliable emission data for these metcils from this source. 

The metal emissions from the 381 m stack depend on production and 
increase proportionately with the sulphur dioxide emissions. This dependence 
and a relative abundance of pertinent data enabled development of correlations, 
which were then used to estimate annual emissions of copper, nickel, and iron 
from the 381 m stack. An insufficient number of tests at other Sudbury sources 
was the reason that no similar correlations for those sources were produced, 

7.1 THE INCO 381 M STACK 



The best estimates of average hourly emissions of major metals from the 
381 m smokestack in the period from 1973 to 1980 are shown in Table 10. 

The iron, copper, and nickel emissions shown in this Table were calculated on the 
basis of yearly sulphur dioxide emissions from straight line correlations between 
the measured emissions of each metal and sulphur dioxide (the measured 
emissions of these metals are shown in Table 11). The straight lines with the 
limits of standard errors of estimates and the associated frequency distribution 
of errors graphs are shown in Figures 7 through 12. 



- ^9- 



TABLE 10: AVERAGE EMISSIONS OF FIVE MAJOR 

METALS FROM THE INCO 381 M STACK 

IN KILOGRAMS/HOUR 



Year 


Iron* 


Copper* 


Nickel* 


Lead 


Arsenic 


1973 


127 


31 


29 


21 


U 


197^ 


163 


39 


37 


29 


10 


1975 


166 


39 


38 


23 


23 


1976 


169 


39 


39 


12 


15 


1977 


156 


37 


35 


18 


8 


1978 


52 


1^ 


12 


10 


- 


1979 


23 


8 


6 


- 


- 


1980 


89 


22 


21 


3^ 


10 


1981 
Average 


73 


19 


17 






113 


28 


26 


21 


13 



•Emissions calculated from regression lines 



The straight-line correlations were selected after several linear and 
nonlinear functions were examined for the goodness of fit through the measured 
data points plotted on graphs. Among the linear functions, polynomials of up to 
fifth order were studied. In comparison to the straight lines, the polynomials of 
higher order were either very similar to the straight lines or unsuitable in that 
they overfit the data points. Among the nonlinear functions, the exponential 
correlations resulted in improved correlation coefficients, but also in poorer 
distribution of errors than the straight-line correlations. The average emissions 
of the three metals calculated from the exponential correlations over the eight 
years from 1973 to 1980 were lower than the corresponding emissions calculated 
from either the straight lines or the average measured values. However, when 
the errors ot estimates were taken into account, no significant difference in the 
values estimated from either function could be found. In this situation a choice 
of the mathematically simpler straight lines was justified. The estimates of 
emissions from the straight-line correlations as shown in Table 10 are more 
representative of the actual emissions than the mathematical averages of 
measured emissions shown in Table 1 1 because they were normalized with 
respect to the production rates. 



- 50- 

The scatter of individual data points about the lines in Figures 7, 9 and 1 1 
is admittedly large, but also understandable in the light of variations in 
particulate composition, process operation, sulphur dioxide emissions, and the 
measurement errors which could all contribute to its magnitude. Errors are 
associated with the estimates from these lines and they must be taken into 
account when interpreting the calculated emissions. Distribution of errors of 
estimates about these straight lines seem skewed, suggesting that a lognormal 
analysis could be appropriate. It must be also ensured that no significant 
changes in the process have taken place, if the emissions beyond 1980 are 
calculated from these straight lines. Better correlations with less scatter were 
obtained in the case of metals versus particulates, indicating consistency in the 
chemical analyses of the emission samples. 

Attempts to correlate arsenic and lead emissions with sulphur dioxide were 
unsuccessful in that their emissions were inversely proportional. One of the 
possible reasons for this unexpected result is nonquantitative collection of these 
species during particulate emission measurements. A special sampling method 
for arsenic, selenium and mercury was employed in the 1980 sampling program, 
but the results did not indicate large differences from the past programs. 

Measured average emissions of all species in particulate form, including 
metals, are shown in Table 11. 

In-plume measurements of metal emissions *'om the 381 m stack were 
performed simultaneously with the in-stack measurements in 1977 (11, 15). The 
results from these tests were comparable, except for arsenic with higher 
emissions measured in a colder plume. A similar comparison attempted in 1980 
resulted in larger discrepancies, with the in-plume method yielding several times 



3I.U 

m 



m 
m 



2i.ni 



□ 



m 



is.n 



ii.n 



X 



E3 s.H 

I 



E(FE) = E(5D2) X 0.00IG5 - 0.0HBa3 
CnRRELRTIQN CDEFFICIENT = a.H3 

bTHNDRRD ZRKUii DP ESTiMfiTE CSX/Y 5 
= * li: . 1 ZBE 



X 



^ 



•* 



■■r-r-t 




1 
sjn 






StQni>RHPBnBSRnVHBISHBi 



5D2 EM 1 55 1 DN ( TDNNES/H ) 

figure: 7. IRDN V5 5UL.PHUR DIDXIDE: EMi55mN5 



mi 

OUTS 

II 


SRa. 

2B.E 






















9 
8 


S.7 
22.9 






/^ 


\ 




7 


a.i 




/ 




\ 




e . 


17 1 




/ 




\ FE V5 snz 




K 


IH.3 




/ 






\ 




H 


ll.H 


/ 








\ 


* 


3 


B.6 


/ 






■ 




\ 




1 • 


S.7 
2.9 


^ 


A 


f 










^ 


^ 




1 * — W7n — ■ — 

B 

• 


— 1 • • ■ I ■ 1 — - -1 

B B i i ■ B B B 

M 5 f -• •- a «- H 




Cn.L LIMITS xia"^ 




F [ 


iURE 


B. 


PRE 


QUENCH 


' D 5TR BUT DN DF ERRDR5 


FDR RON V5 





5ULPHUR DIDXIDE EMISBIDNS 





IS.Ut 


r^ 


iH.n 


r^ 






i3.n 


PI 




3: 


i2.n 


m 


ii.n 


Ul 




n 


ii.n 


'^ 






9.ni 


r^ 






B.n 


-i 




LJ 


7.11 


'^^ 




rM 


B.H 


m 


KM 


T 






H.n 


X 




^- 


a.n 


ta 




1 


2.n 



Eccu) - E(5n2) X H.iaiaaiE - la.iaiaBia 

CDRRELRTIDN CDEFFICIENT - 0.SB 

STRNDHkl: EhKDH Df EbTiMfiTE C^X/Y ) 



+ 







5D2 EM I SB I DN ( TDNNE5/H ) 

FIGURE g. CDPPER V5 SULPHUR DIDXIDE EM 155 1 DNS 



CU V5 5D2 










COL LIHITS XII 



r2 



FIGURE 10. FREQUENCY D15TRIBUTIDN DF ERRDR5 FDR CDPPER V5 

SULPHUR DIDXIDE EMI 55 1 DNS 



II.Mt 



BM 






C3 



□ 



m 
in 



6.M 



s.n 



I.H 



3.N 



X 2.n 



IS] 



r!i I.I 



E(N1) - E(5a2) X 0.00037 - 0.01009 
CORRELRTIQN CDEFFKIENT = 0.SB 

STRWDRRD ERROR DF ESTiHRTE (5x/Y ) 
= i0.01EH 



+ 







i ■ • 



B R n f 



• • 



9 H B P B n 



FIGURE 



5D2 EMISSION ( TDNNES/H ) 

. NICKEL. V5 SULPHUR DIUXIDE EMIBBIDNB 



(Hi. 
OUNTS 


iRa. 


9 


2S.7 


B 


22.9 


7 • 


2IJ 


E 


17.1 


S- 


IH.3 


H' 


ll.H 



a B.E 



Z S.7 



Nl V5 5D2 




ON 



COL UNITS XII 



-2 



FIGURE 12 



FREQUENCY DISTRIBUTION DF ERRURS FDR NICKEL V5 
SULPHUR DIDXIDE EMI55IDN5 



TABLE 11: AVERAGE MEASURED EMISSIONS OF METALS AND OTHER PARTICULATE 
POLLUTANTS FROM THE INCO 381 M STACK IN KILOGRAMS/HOUR 



Year 


Iron 


Copper 


Nickel 


Lead 


1 
Aluminum 


Arsenic 


Zinc 


Chromium 


Selenium 


Cadmium 


1973 


228 


65 


^8 


21 


18 


11 


1 
6 


6 


6 


^^ 


1974 


258 


55 


55 


29 


6 


10 


7 


15 


6 


5 


1975 


(>h 


27 


15 


23 


f 


23 


11 


0.5 


6 


0.8 


1976 


7h 


25 


22 


12 


3 


15 


7 


0.2 


- 


1 


1977 


lif2 


^I 


33 


18 


9 


8 


11 


2 


- 


1 


1978 


80 


20 


20 


10 


- 


- 


1 




- 


- 


1979 


31 


13 


12 


- 


- 


- 


- 


- 


- 


- 


1980 


1^*7 


h7 


t*h 


3h 


19 


10 


6 


2 


3 


2 


Average 


128 


37 


31 


21 


10 


13 


7 


h 


5 


2 



I 

I 



Emission rates of mercury were measured in 1980 at 7 grams per hour. 



TABLE 11 (CONTINUED): AVERAGE MEASURED EMISSIONS OF METALS AND OTHER 
PARTICULATE POLLUTANTS FROM THE INCO 381 M STACK IN KILOGRAMS/HOUR 



Year 


Bismuth 


Beryllium 


— -1 
Manganese 


Tin 


Antimony 


Strontium 


Silver 


Vanadium 


Lithium 


Silicon 


1973 
197^ 
1975 
1976 
1977 
1978 
1979 
1980 


3 
3 
2 
1 
5 


2 


1 
2 

0.2 
0.1 

OA 

0.3 


0.8 


0.6 


0.* 
0.1* 


0.3 
0.1 


0.2 

0.1 

1.0 


0.1 
0.6 


. 

109 

1 
19 

1^ 

i 

32 

t 


Average 


3 


2 


0.7 


0.8 


0.6 


0.5 


0.2 


0.^ 


0.3 


43 



cr 



• t 



• » 



* • 



• « 



TABLE 11 (CONTINUED): AVERAGE MEASURED EMISSIONS OF METALS AND OTHER 
PARTICULATE POLLUTANTS FROM THE INCO 381 M STACK IN KILOGRAMS/HOUR 



■ 




.. 


i 






1 






Year 


Magnesium 


Boron 


Calcium 


Tellurium 


Cobalt 


Molybdenum Titanium 


Potassium 


Sodium 


1973 


15 


10 


9 


0.3 






" 


, 




[97ti 


5 


- 


5 


- 


2.0 


f 


- 


- 




1975 


1 


- 


3 


- 


0.3 


- 


- 


- 


- 


1976 


- 


- 


- 


- 


0.1 


0.1 


1 


t* 


20 


1977 


6 


- 


7 


- 


1.0 


- 


- 


3 


2 


1978 


^ 


- 


- 




- 


- 


- 


- 


- 


1979 


- 


- 


- 


- 


0.3 


- 


- 


- 


- 


1980 


^ 




- 


- 


2.0 


- 


- 




- 


Average 


6 


10 


6 


0.3 


0.9 


2 


1 


3 


11 






- 58 - 

lower emissions for most metals. Arsenic was again an exception, with much 
higher emissions measured by the in-plume method. 

From among the five major metals, iron, copper, and nickel tend to be 
emitted in larger sizes, with mass medium diameters of more than 13 um, while 
the more volatile lead and arsenic are much smaller in size, with MMDs of about 
1 um (35). 

7.2 THE INCO 194 M STACK 

The iron ore recovery plant and the nickel refinery are the only plants 
contributing metals to the 194 m stack emissions (the acid plant emissions are 
essentially metal-free). The combined emissions of iron, nickel and copper from 
these two processes are as large as those from the 381 m stack. Iron is 
largely emitted from the iron ore recovery plant, while copper and nickel are 
mostly contained in the nickel refinery emissions. In-stack emission 
measurements at all plants - iron ore recovery, nickel refinery and sulphuric acid 
plants - were performed only on one occasion in 1976, consequently, no 
dependence of emissions on production can be illustrated. Rather, the 
production rates during the measurements, as shown in the relevant Inco reports 
(9, 10), will be given. In addition to these in-stack measurements from 1976, 
there are 1979 in-plume emission data available for comparison of the two 
methods; this is illustrated in Table 12 (28). 

As will be discussed later, the in-stack measurements were not performed 
according to strict testing procedures, and the results could be in error. In the 
case of copper and nickel they are probably too low. The in-stack and the in- 
plume measurements were not conducted simultaneously, but since the two 
processes were operated at similar production rates during these measurements, 



- 59- 



TABLE 12: COMPARISON OF IN-STACK AND IN-PLUME 
AVERAGE EMISSIONS IN TONNES/DAY 



Method 


Sulphur 
Dioxide 


Iron 


v^opper 


Nickel 


Lead 


Arsenic 


In-stack 1976 


150 


1.8 


0.5 


0.6 


0.01 


0.01 


In-plume 1979 


190 


0.8 


0.2 


0.5 


0.01 


O.OU 


In-stack 
In-pIume 


0.8 


2.2 


2.5 


1.2 


1 


0.25 



the emissions obtained by the two methods can be compared. As already 
discussed, the in-plume method produced relatively lower emissions of iron, 
copper and nickel, and higher emissions of arsenic. 

Emissions of metals (in-stack measurements) from the iron ore recovery 
and nickel refinery plants are shown in Table 13. Emissions from the iron ore 
recovery plant are continuous, and the corresponding values Irom Table 13 can 
be prorated to any time period. As far as representativeness of emissions is 
concerned, similar comments to those made in the discussion of particulate 
emissions from this plant apply. The sampling method employed in the emission 
measurements was not rigorous enough to ensure collection of representative 
samples and large errors in the emissions as shown in Table 13 are possible. 



The emissions from the nickel refinery may also be in error and are 
probably too low. These emissions are not continuous; they originate in nickel 
converting, which is a batch process. In calculating the emissions in Table 13, it 
was assumed that 3.06 batches of 70 tonnes of charge, each of ^.5 hours 
duration, were processed in a day. In order to obtain approximate actual 



TABLE 13: EMISSIONS OF METALS FROM THE IRON ORE RECOVERY 
AND NICKEL REFINERY PLANTS IN KILOGRAMS/DAY 



Plant 


Iron 


Copper 


Nickel 


Lead 


Arsenic 


Selenium 


Cobalt 


Iron Ore 
Recovery 


169^ 


7 


^8 


1 


1 


0.1 


0.9 


Nickel 
Refinery 


67 


^61 


581 


15 


8 


3 


11 


Total 


1761 


U$ 


620 


16 


9 


3 


12 

1, ,' 



I 

o 
ft) 

'i. 



TABLE 13 (CONTINUED): EMISSIONS OF METALS FROM THE IRON ORE 
RECOVERY AND NICKEL REFINERY PLANTS IN KILOGRAMS/DAY 



Plant 


Chromium 


Manganese 


Silver 


Cadmium 


Aluminum 


Magnesium 


Calcium 


Iron Ore 
Recovery 


8 


3 


0.7 


0.2 


- 


- 


- 


Nickel 
Refinery 


7 


1 


5 


2 


1 


0.5 


1 


Total 


15 


^ 


6 


2 


- 


- 


- 



I 



-61 - 

emissions per batch, the emissions in Table 13 must be divided by 3.06. Metal 
emissions are not uniform throughout the batch and they change in each of the 
three cycles - charging, blowing and reduction. In comparison to nonvolatile 
metals such as iron, copper, and nickel, which are mostly emitted during 
charging and blowing, half of the more volatile lead and arsenic are emitted 
during reduction. 

7.3 LOW LEVEL EMISSIONS FROM THE INCO SMELTER BUILDING 

Except for copper, which is emitted in considerable quantities in 
unconfined or fugitive emissions from the copper converters, the low level 
emissions from the Inco smelter building are relatively small contributors to the 
total emissions of metals in the Sudbury Basin. The low level metal emissions as 
mocisured simultaneously with the particulates were prorated to a typical 
production of nickel bessemer matte and blister copper (12, 14, 17, 20, 21) and 
the prorated emissions from various process steps are shown in Table 14. 

The accuracy of these emission measurements was low, for reasons already 
discussed under particulate emission measurements, hence, the degree of 
representativeness of emissions in Table 14 is not known. However, they are the 
best measurements presently available and at least accurate enough to confirm 
what was suspected before; that is, in comparison to the other sources discussed 
in this report, the low level emissions from the smelter building are not a 
significant contributor to the total metal emissions in the Sudbury Basin, with 
the exception of copper. 

7.4 THE FALCONBRIDGE 93 M STACK 

Emissions of metals from the Falconbridge smelter were measured with 



TABLE it*: AVERAGE LOW LEVEL EMISSIONS OF METALS IN KILOGRAMS 

FROM THE INCO SMELTER AT COPPER CLIFF DURING TYPICAL PRODUCTION RATES 

OF NICKEL BESSEMER MATTE AND BLISTER COPPER IN KILOGRAMS/DAY 



Process 


Iron 


Copper 


Nickel 


Lead 


Arsenic 


Cobalt 


Zinc 


Cadmium 


Selenium 

■ 


Copper converters 


82 


602 


50 


- 


- 


1.0 


- 


- 


- 


Nickel converters 


27.9 


19 


22.^ 


0.2 


0.1 


0.86 


0.2 


0.01 


0.03 


Nickel reverberatory 
furnaces 


27.2 


5.2 


8.0 


J* 


T* 


0.31 


T* 


- 


T* 


Multiple hearth 
roasters 


57.0 


^.7 


12.1 


J** 


*[■** 


OAi 


T** 


I"** 


T** 


Copper flash 
furnace 


5.7 


8.2 


0.3 


1.5 


0.01 


0.01 


0.61 


0.3 


- 


Total 


199.8 


639.1 


92.1 


1.7 


0.11 


2.6 


0.81 


0.31 


0.1 



T* Total Emissions of Lead, Zinc, Cadmium, Bismuth, Arsenic, and Selenium estimated at 1 Kg/D (17) 
T** Total of Lead, Zinc, Cadmium, Bismuth, Arsenic, and Selenium emissions - 1,33 Kg/D (21) 






-63- 

both old and new smelting processes on line. The results suggested that there 
was a significant decrease in emissions of at least the major metals occurred 
after the installation of the new process in 1978, Admittedly, the measurement 
methods prior to 1978 were not as accurate as the multipoint in-stack sampling 
executed at the 93 m stack in 1978, and the results may be in error. In 1973, an 
in-stack-single-point grab sample was taken (23), while a comprehensive in- 
plume method wcis employed in 1977 (15). The in-plume method can also 
underestimate the emissions of nonvolatile metals, as discussed under the metal 
emissions from the 19^ m stack; hence, the emissions of these metals from the 
old process could have been even higher than measured and shown in Table 15. In 
spite of this possible underestimation, it is clear from Table 15 that the metal 
emissions from the smelter have been significantly reduced after the installation 
of the new process. 

There is a degree of similarity in the size distribution of metals emitted 
from the Falconbridge 93 m and Inco 381 m stacks; iron, nickel and copper are 
emitted at a larger size than the more volatile lead and zinc. However, in terms 
of absolute size, all metal particles from the Falconbridge stack were smaller, 
with the mass median diameters for iron, nickel and copper ranging from 3.0 to 
7.0 micrometers (26) and 0.5 to 0.9 micrometers for lead and zinc; comparable 
values at the Inco 381 m stack were larger than 13.0 micrometers for non- 
volatile metals, and 0.5 to 4.0 micrometers for lead and zinc. 

No correlation or dependence of metal emissions on production at the 
Falconbridge smelter can be shown because of an insufficient number of 
measurements. 



TABLE 15: EMISSIONS OF METALS FROM THE FALCONBRIDGE 93 M STACK IN KILOGRAMS/DAY 



Method 


Iron 


Copper 


Nickel 


Lead 


Arsenic 


Selenium 


Zinc 


Aluminum 


Manganese 


Cadmium 


Magnesium 


Calcium 


In- stack 
1979 


270 


31 


25 


37 


IS 


- 


8 


20 


0.3 


6 


11 


9 


Standard 
Deviation 


202 


25 


19 


21 


16 


- 


3 


23 


0.2 


3 


8 


6 


In- plume 
1979 


115 


28 


19 


34 


151 


- 


5 


24 


0.7 


2 


- 


- 


In- plume 
1977 


2310 


384 


269 


140 


441 


8 


56 


- 


13 


- 


- 


- 


In- stack 
1973 




809 


920 


1240 


140 


- 


- 


- 


- 


- 


- 


- 


- 



-65- 
8. EMISSIONS OF SULPHURIC ACID 

The difficulties inherent in determining sulphuric acid in emissions from 
mineral processing were already discussed in the description of sampling 
methods. Consequently, a possibility exists that some of the measured 
emissions, with the exception of acid plants, are in error. This possibility was 
recognized after detailed analyses of test data, which were not always consistent 
with either theoretical expectations or other measurement programs (^, 11). In 
most instances, inconsistencies were traced to improper sampling conditions and 
low sampling temperatures which allowed condensation of sulphuric acid on 
particulates and, hence, possible formation of artifact sulphates. Sulphates 
including those of artifact origin, were excluded from the calculations of acid 
emissions, and so calculated emissions could have been underestimated. The 
total sulphate emissions from the 381 m stack were in some tests as large as the 
sulphuric acid emissions (16). There are no similar interferences in the acid 
plant emissions, and these emissions can be considered accurate. 

Depending on the source, the acid emissions account for OA to 3,0 percent 
of the total sulphur dioxide and acid emissions. In the Inco 381 m stack and the 
Falconbridge 93m stack emissions, these percentages range from OA to lA, 
while in the Inco 194 m stack, the percentage is higher at atwut 3%. The largest 
source of acid emissions is the 381 m stack, contributing about 77% to the total 
of 25.9 tonnes of acid per day from all major sources in Sudbury, as indicated in 
Table 1. 

Hourly emissions from cdl sources are shown in Table 16. 



-66- 



TABLE 16: ACID EMISSIONS FROM MAJOR INDUSTRIAL SUDBURY 
SOURCES IN TONNES/HOUR 



Year 


Inco 381 m 


Inco 194 m 


Inco Smelter 


Falconbridge 93 m 




Stack 


Stack 


Low Level 


Stack 


1973 


0.63 








197^ 


1.04 








1975 


1.66 








1976 


- 






,' 


1977 


0.37 


0.19 






1978 


- 




0.01 




1979 


0,7i^ 






0.05 


1980 


0.52 








Average 


0.83 


0.19 


O.OI 


0.05 



Add emissions from the 381 m smokestack were not always consistent with 
sulphur dioxide emissions. Sulphur dioxide emissions were higher in 1977 than in 
1973 when acid emissions were higher, thus causing problems in developing a 
satisfactory correlation between the emissions of these two species. However, 
data from 1973 through 1976 suggest that the emissions of these two species 
increase simultaneously (1 through 7). 

From among the three processes contributing to the 194 m stack emissions, 
the acid plants are the most significant source of acid. Combined emissions 
from the three acid plants were 0,1325 tonnes per hour, representing about 71% 
of the total to the stack, followed by the nickel refinery with 0.044 tonnes per 
hour, and the iron ore recovery plant with 0.01 tonnes per hour. Emissions from 
the nickel refinery are not continuous, and the daily maximums occur in three 
one- hour periods. 



Determination of sulphuric acid in the Inco smelter low level emissions was 
not complete in that no satisfactory measurements were performed at the nickel 
and the copper converters. No sulphuric acid was found in the fugitive emissions 
from the roasters. The emissions listed in Table 16 include only the 
reverberatory furnaces and the copper flash furnace. 



- 67- 

9. REFERENCES 



1. Interim Report on the Inco 1250 Foot Stack Emission Study, Air Resources 
Branch, November 23, 1973. 

2. Smelter Roof Monitor Emissions 197^ Campaign, Inco Process Technology, 
Smelter Project No. 0^7 J, March 10, 1975. 

3. Superstack Emissions Monitoring 197^ Campaign - Comparison of Single vs. 
Multi-point Sampling, Report, Inco Process Technology, Smelter Project 
No. 0^7.6, March 10, 1975. 

k. Determination of Sulphuric Acid in Stack Gas, report, Inco Process 
Technology, Smelter Project No. 0^7.9, March 2k, 1976. 

5. Superstack Emissions Monitoring 1975 Campaign, Comparison of Single vs. 
Multi-point Sampling, Report, Inco Process Technology, Smelter Program 
No. 0^7-10, April 1^*, 1976. 

6. Report on a Source Test at 1250 Foot Inco Stack on June 11, 1975, Air 
Resources Branch, Report 07-75, September, 1975. 

7. Acid Particulate and Particle Sizing Sampling at Inco Superstack, Sept., 

1976, Air Resources Branch Report No. ARB-TDA-39-77, May, 1977. 

8. Tail Gas Analysis Report by C. Cordon, K. Payne, R. Knapp, C.I.L. Report 
1977. 

9. Determination of the Quantity and Nature of Emissions from the NRC 
Main Flue to the lORP, Report, Inco Process Technology, Project No. 
^1^.8, January 10, 1977. 

10. Iron Ore Recovery Plant Main Flue Sampling Report, Inco Process 
Technology, lORP, Project No. 226.1^, January 1^, 1977. 

11. Acid Particulate and Particle Sizing Sampling at Inco Superstack, June, 

1977, Air Resources Branch, Report No. ARB-TDA-53-78, February, 1978. 

12. Monitoring of Fugitive Emissions of SO , Particulates in no. 15 Copper 
Converter Ventilator, Report, Inco Process Technology, C.C, Smelter 
Project No. 0^7.12, June i, 1978. 

13. Smelter SO^ Emissions Summaries, Letter from Falconbridge to M.O.E. 
Sudbury District Office, December 15, 1977, April 26, 1977 and December 
29, 1979. 

ik. Monitoring of Fugitive Emissions of Sulphur, Particulate and Acid Mist in 
No, k Converter Roof Ventilator, Report, Inco Process Technology, Smelter 
Project No. 0^7.12, November 9, 1979. 

15. Airborne Investigations of the Inco and Falconbridge Stack Plumes, 1976 - 
77, Air Resources Branch, Report No. ARB-TDA 60-79, May, 1979. 



-68- 
09. REFERENCES (Cont'd) 



16. 380 m Chimney Emissions Monitoring - 16 Particulate and Acid 
Determinations (July - October, 1979), Report, Inco Process Technology, 
C.C. Smelter Project No. 0*7.17, December 18, 1979. 

17. Measurement of Fugitive Emissions of Sulphur Dioxide, Particulates and 
Sulphuric Acid from Nickel Reverbertory Furnaces, Report, Inco Process 
Technology, Project No. 0*7.12, March 19, 1980, 

18. Particle Size Determinations at the 380 M Chimney, Inco Smelter, Copper 
Cliff, Ontario, Air Resources Branch, Report No. ARB-TDA-*3-80, 3une, 
1980. 

19. Size Distribution and Emission Rate Measurements of Particulates in the 
93 M Falconbrdige Smelter Stack Plume, 1979, Air Resources Branch, 
Report No. ARB-TDA 57-80, August 1980. 

20. Measurement of Fugitive Sulphur Dioxide, Particulate and Sulphuric Acid 
Emissions from Copper Flash Furnace, Report, Inco Process Technology, 
Project No. 0*7. 12A, November 19, 1980 

21. Measurement of Fugitive Sulphur Dioxide, Particulate and Sulphuric Acid 
Emissions from Multiple-Hearth Roaster, Report, Inco Process Technology, 
Project No. 0*7- 12B, December 9, 1980. 

22. Determination of the Extent of Particulate Stratification at the Inco 381 
Meter Chimney at Copper Cliff, Ontario, Air Resources Branch, Report 
No. ARB-TDA-58-80, December, 1980. 

23. Falconbridge Co. Source Testing 1973, 197* - Smelter Stack, ARB Files, 
3uly 19, 1978. 

2*. Report and Recommendations of Provincial Officer for Inco Limited 
Operations in the Regional Municipality of Sudbury, Ministry of the 
Environment, June 21, 1978. 

25. Iron Ore Recovery Plcuit, No. 2 Pellet Stack Sampling, Inco Process 
Technology, Project No. 226.16, November 1979. 

26. Sulphur Dioxide, Sulphuric Acid, Particulate and Particle Size 
Determinations at Falconbridge Smelter Stack, August, 1979, Air 
Resources Branch, Report No. ARB-TDA-*0-80, December, 1980. 

27. Feasibility of Controlling Low Level Emissions from the Copper Cliff 
Smelter Complex, Inco Process Technology, Project No. 0*7.21, December 
15, 1981. 

28. Size Distribution and Emission Rate Mesurements of Particulates in the 
Inco 381 M Chimney and Iron Ore Recovery Plant 1979-80, Air Resources 
Branch, Report No. ARB-TDA-62-80, September, 1980. 

29. Comments on Emission Testing Reports Prepared by Inco Smelter Process 
Technology, Memoranda to Files, 1977, 1978, 1980, Air Resources Branch. 

30. Evaluation of the Modified TBRC Off-Gas Cleaning System; Effect on 
Nickel Emissions to lORP Stack, inco Source Testing, July, 1980. 



-69 - 



31. Information on Copper Cliff Smelter Electrostatic Precipitators, Letter 
from Inco Environmental Control to Northeastern Region of the Ministry of 
the Environment, February 21, 1981. 

32. 381 Metre Chimney Continuous SO- Monitors - Progress Reports #13 and 
//l^f, Inco, December ^, 1981, Nortneastern Region Files, Ministry of the 
Environment. 

33. Air Resources Branch Files, Working Notes, 1982. 

34. Quarterly Reports from Inco to Sudbury District Office of the Ministry of 
the Environment. 

35. Airborne Particulate Size Distribution Measurements in Nickel Smelter 
Plumes, W. H. Chan et al., for Submission to Atmospheric Environment for 
Publication, Mar. 1982. 

36. Ontario Source Testing Code, Report //ARB-TDA-66-80, November 1980, 
Ministry of the Environment. 

37. Code of Federal Regulations, 40 CFR53.4, Protection of Environment, 
Revised as of 3uly 1, 1980, Method 5, Office of the Federal Register, 

U.S.A. 

38. Information provided by L. Fitz of the Northeastern Region of the Ministry 
of the Environment, Air Resources Branch Working Notes, 1982. 

39. Sudbury Environmental Study, Atmospheric Research Program. A Synopsis. 
Report y/ ARB-27-82-ARSP, September, 1982. 



<:B6T 

ax